Boris Johnson’s style of government is “contrary to a decent, proper conservatism”, Conservative MP for Hereford and South Herefordshire Jesse Norman writes in the Financial Times (‘Britain under Boris Johnson has abandoned ideals of political leadership’) this morning.

The MP’s letter of no confidence in the Prime Minister on Monday came just before a narrow vote by Tory MPs to keep Mr Johnson in place.

Mr Norman describes Mr Johnson in his piece as “a man I have known and greatly liked for more than 40 years”, but says his concerns “relate to policy, approach to government and treatment of the British constitution” in addition to the recent Partygate scandal.

“All are contrary to a decent, proper conservatism,” he says, and accuses Mr Johnson “doubling down, indulging an almost atavistic urge to provoke culture wars” since the vote, rather than addressing MPs’ concerns.

Mr Norman’s earlier letter to the PM described the Government’s policy of holding immigration candidates in Rwanda was “ugly, likely to be counterproductive and of doubtful legality”, while plans to privatise Channel 4 were “unnecessary and provocative”.

A scholar of political thought and history, Mr Norman says today that Britain has historically relied on “good chaps” in government to behave virtuously rather than being constrained by a formal constitution.

“It is as though the Prime Minister and some of his senior colleagues have declared themselves exempt from the obligations of the good chap theory, but without any validating wider mission or purpose,” he writes.

He calls for “a renewed public understanding of the best of our civic values and our history,” adding: “Real leadership from a future occupant of Number 10 would help.”

Meanwhile, in a Commons debate yesterday on the role of Ofwat, the water companies watchdog, Mr Norman called for a “national rivers recovery fund” paid for from fines levied on river polluters, including water companies.

“At the moment, small fines go back into redress for pollution, but large ones go to the Treasury. My former colleagues [Mr Norman is an ex-Treasury minister] will not thank me for it, but there is a case for a wider national recovery fund for rivers.”

Part of the problem with the river Wye in particular “is that it crosses the border, so there is an impunity in that Wales can avoid having regulatory involvement and leave the muck to come down to Herefordshire”, Mr Norman said.

An “all-river strategy with [its own] commissioners, as there have been since the 18th century on the Tweed, might be a solution to the problem”, he suggested.

Concluding the debate, environment minister Rebecca Pow MP said: “The message has been clearly sent that Ofwat must reduce the harm from storm sewage overflows.

“We will no longer stand poor performance from the water companies.”

Untreated sewage was discharged into English and Welsh watercourses over 350,000 times in each of the last two years, official figures show.

Campaigning group Wild Justice said today it had passed its target to raise £40,000 to fund pursuing a judicial review at the High Court of Ofwat's failure to regulate sewage discharges.